Liquid-fuel burner



C). FALKENWALDE ET AL.

LIQUID FUEL BURNER Filed Feb. 13. 1.922 2 Sheets-Sheet l O., FALKENWALDE ET Al.

LIQUID FUEL BURNER Filed Feb. 13. i922 2 Sheets-Sheet. 2

Patented oe. 21, 1924.

UNITED STATES OSCAR FALKENWALDE ANI) CHARLES 0. FALKENWALDE, OF BALTIMORE, MARYLAND.

LIQUID-FUEL BURNER.

Application ledFebruary 13, i922. Serial No. 536,046.

To all cri/1.0m t may concern.'

Be it known that we, Osciin FALKENwALDn and CHARLES O. FALKENWALDE, citizens Vof the United States of America, both residents of the city of Baltimore, State of Maryland, have invented certain` new4 and useful Improvements in Liquid-Fuel Burn ers, of which the following is a specification.

In accordance with our invention the liquid fuel is changed int-o a saturated vapor superheating being avoided to prevent carbonizat-ion and premature cracking of the fuel. From the vaporizing chamber, the

Vsaturated vapor is led to a nozzle from which it is projected through an air mixer where it burns producing a blue flame, the burning vapor being projected forward from the mixer 'into contact with the outer walls of the vaporizing chamber which is so formed as to `act as a second air mixer. Contact of the flame with the vaporizing chamber at this' point supplies the heat for' the vaporization of the fuel in the normal operation of the burners. It also serves to cool the jet or flame to a considerable degree and in connection with the new air supply to so change the process of combustion that a new and more highly combustible mixture including carbon monoxide, unfixed hydrocarbons and air is formed and projected forward into the converter or combustion chamber which is beyond the vaporizing chamber, i. e., on the opposite side thereof from the nozzle. This converter becomes heated to :a high; degree. When the converter becomes heated the character of combustion going on is changed to the er.- tent. that combustion apparently becomes complete, the carbon monoxide being completely burned together with the othergases produ-cing an intense heat with flames projecting from the perforated walls of the converter for a distance of from 12 to 15 feet, the fuel consumed being small out of all proportion to the size and intensity of the lire and lthe amount of heat generated.

The burner described has in many in stances been used in melting asphalt pitch and mastic requiring a temperature of over 5009 F., 4and for this Ypurpose a little over a gallon of oil to a barrel of pitch is vfound suliicient on account of the extreme efficiency of the burner.

In the accompanying drawing we have illustrated a burner embodying' our invention in the preferred form. In the drawings:

Figure l is a plan of the entire apparatus;

Figure 2 is a side elevation;

Figure 3 is an end elevation, the pipes at the left of Figure 2 being sho-wn in section;

Figure 1- is a section on the line f-l of Figure 2';

Figure 5 is a section on the line 5--5 of Figure 3 showing the vaporizer only;

Figure 6 is a section through the nozzle taken on the aXis of the same.

Referring to the drawings by numerals, the apparatus shown includes a nozzle 1, first air mixer 2, second air mixer and vaporizing chamber 3 and converter More particularly the vaporizing chamber and second air mixer 3 as shown are in the form of two tubular members 5 6 parallel to each other and enclosing a central space kor aperture through which the burning vapor projected from the nozzle 1 passes.k

As shown Ithe tubular members 5-6 are each in the form of a hollow square though ,this shape is not considered essential and they are connected by two passages 9-11. VThe chamber las shown is `provided with clean-out holes closed by screw plugs 12 and surrounded by bosses 13. The two portions 5 and 6 ofthe chamber 3 are spaced apart as illustrated providing an air pas sage 19 which is bridged by the connecting" passages 9-11, the rush of the vaporized fueland air through the opening 7 draws heated air in through the air passage 19 mixing it with the fuel and constituting the second mixing operation as hereinafter described.

Liquid fuel issupplied to the vaporizing chamber by way of a pipe lll which as evaporating chamber 8 in a direction opposite to the converter 1, i. e., to the left in Figures 1 and 2 is the vapor pipe 17. This is provided with a return bend, i. e., a bend of 180o indicated by reference character 18 and it terminates beyond the bend in the nozzle 1 which is directed backward toward the evaporating chamber being in direct alignment with the center of the opening 7 through the vaporizing chamber'.

Between the nozzle 1 and the vaporizing chamber and in alignment with the nozzle is the .first air mixer 2, said mixer consisting of a cylindrical portion 21 having' its axis in alignment in the axis of the nozzle and terminating on the side remote from the nozzle in a frusto-conical portion 22 giving the mixture a reducing taper at the end. This mixer 22H22 is carried on an arm 23 which projects from a collar 24 which encloses and slides on the vapor pipe 17. This may be held in adjustment. by set screw 25. The collar 2li and the arm 23 are for the purpose of providing an adjustment of the first air mixer in the direction of the axis of the nozzle, fuels of different specific gravity fed at different pressures requiring` different adj ustments.

The converter 1l is as aforesaid on the side of the vaporizing chamber opposite to the nozzle. Tt is not necessarily in exact alignment therewith, but it has an open end 37 turned toward the nozzle, the converter which as shown is in the form of a hollow cylinder having its axis parallel to the' axis of the nozzle, the cylinder being in a. position to receive the vapor as projected from the nozzle. The center of the cylinder as shown is somewhat above the line of the nozzle so that the jetor flame enters the chamber near the bottom. j

Though the converter chamber as shown is cylindrical the exact form is not essential. In this instance it is formed of two semi-cylindrical sections 30 and 31 flanged at their lateral edges at 32 and 33, the flanges being secured together by means of bolts or suitable means 34k and the chamber being supported on a suitable bracket or legs 35, the top section SOis provided with large perforations 36 uniformly distributed and occupying aboutV half the area. The converter is open at the end toward the nozzle indicated by reference character 37 and closed at the remote end forming a back wall 38. There is also a pan or basket l() of V shaped cross-section which encloses the vaporizing chamber from beneath and as shown the same is formed integral with the bottom half of the converter, which is preferably also closed, the rigidity of the connection being increased by a web 41. By enclosing the bottom half of the chamber the influx of cold air is prevented and a supply of air for the second mixer is retained in the vicinity of the openings 19. The basket 4() air supplied to the mixer. The basket also overcomes any tendency to deflect the jet and unduly cool the chamber by currents of cold air and any fuel which may be condensed during starting, is caught and retained to be burned later as the temperature of the burner increases. The closing of the bottom of the converter also has the effect of Cutting' off upward drafts, i. e., the tend'- ency to draw air into the converter by oonvection sufficient air for combustion being carried into the converter with the jet.v The converter is preferably made of some material having heat retaining and radiating properties as cast-iron. j Y

To start the burner the valve 15 may be open until the nozzle begins to drip7 then it is closed and the fuel may be lighted at the nozzle to heat the nozzle. As the nozzle becomes heated the fuel will be projected herefrom in the form of a jet burning vapor passing through the first air mixer 2 into the aperture 7`in the if'aporizing cham# ber and second air mixer The latter soon becomes heated and the volume and pressure of the jet are gradually increased up to the point where the fuel in the 'vaporizing chamber begins to be exhausted, when the valve 15 which up to this time has been closed since the filling of the chamber is cracked or opened slightly. From the vaporizing chamber or second air mixer the jet is projected into the converter Ll.

The details of the chamber 3 are of in-v c terest in connection with their influence or effect on theoperation of the device. lt will be noted that the passage 1% enters the bottom of the chamber on the side toward the nozzle and the fuel tends to flow forward through the passage 11 into the forward section or member of the chamber 6. `When the burner is in full operation the fuel is partially vaporized as it enters thel chamber in the bottom portion of the chamber 5 and the vaporized portion rises in the direction of the vapor pipes 17, the main portion of the liquid flows forward into the chamber 6 where it is vaporized and rising, escapes through the passages 9---11 accumulating velocity and pressure which carriesY it forward through the` vapor pipe 17, toward the nozzle 1 from which it escapes at an extremely high velocity forming a conical jet as illustrated.

In normal operation the vapor directly in front of the nozzle is cool, moist and whitish, superheating in the vaporizing chamber 8 being preferably avoided by placing the chamber :in contact with the cooler portion of the flame,ithis prevents cracling and carbonization in the., chamber and in the nozzlevand passages. This apparently also gives increased efficiency. `At the mouth of the conical frustum 22 of the first air mixer the jet of vapor burns producing a blue color or flame but the entire burning mixture passes onward without breaking the form of the jet- Which is substantially conical, with the apex toward the nozzle. The jet as aforesaid extends throughthe aperture 7 in the vaporizing chamber which also acts'as a second air mixer mixing with the jet heated air which is drawn in through the passages 19 between the sections of the chamber, the flame at the same time being cooled down and servingto heat the vaporizing chamber to a moderate degree producing only saturated vapor from the liquid fuel as aforesaid.

Frein the vaporizing chamber aperture 7, the burning mixture enters the converter 4: which when cool produces no apparent eect except that small jets of fiame proj ectV therefrom but as the converter heats up the flame, increases in volume 'and intensity, radiating from the openings 30 to a distance of approximately l5 Yfeet under normal efficient operation producing from a. given amount of fuel heat in greater intensity and quantity as measured by heat units than any apparatus previously known.

While the theory of operation cannot be definitely ascertained it is thought that the cooling` and remixing of the jet with heated air in its passage through the second mixer or vaporizing chamber, followed by the reheating in the converter have the effect of making the carbon monoxide and other gases available for combustion to a greater extent than in the previously known apparatus so that a much greater efficiency results and substantially complete combustion with approximately efficiency in the conversion of the fuel into heat is attained.

It is particularly important that the fuel jet as projected from the nozzle is composed of saturated instead of superheated vapor and that as it issues from the nozzle when the burner is under full operation, it is comparatively cold, that it is then mixed with air at the first air mixer 22, which serves by the velocity of the jet to draw air in and to project it into the jet. Here combustion is started with a blue fiame, then the jet comes in contact with the evaporating chamber 3 at a point comparatively remote from the point of maximum temperature, the heat imparted to it being insufficient to accomplish the superheating or to crack the fuel and that this chamber serves not only to partiallycool the jet but to accomplish a further and second introduction of heated air into the fuel from which point the new mixture is projected into the converter where it burns readily at a very high temperature being in fact a gas containing not only the fuel consisting of carbon monoxide and various hydro-carbons but sufficient air thoroughly mixed therewith and preheated to give complete combustion, the mixture being in fact an explosive mixture which burns as formed and released and the combustion cf which develops the greatest quantity of heat ever obtained from given quantities of fuel, the reduction of the fuel to compounds such as carbon dioxide being practically complete.

The fuel may be any vaporizable petroleum product as kerosene, gasoline, fuel oil or the like, any high degree of refinement being unnecessary or any other combustible liquid as alcohol.

Having thus described a preferred form Vof our invention, We would have it understood that the specific terms herein are used descriptively rather than in a limit ing sense, the scope of the invention being defined in the claims.

What we claim and desire to securel by Letters Patent is:

l. An oil burner comprising a combustion chamber having one of its ends open and the other closed and having an imperforate bottom wall and a perforated top wall, a pan located at the open end of said chamber, a vaporizer having a central opening and located within said pan, the pan being open at the top whereby air may reach the vaporizer, said bottom wall being elevated with respect to the base of the pan, and a nozzle in communication with said vaporizer `and pointing in the direction of said opening.

2. An oil burner comprising a combustion Chamber having one of its ends open and the other closed and.` having an imperforate bottom wall and a perforated top wall, a support for the closed end of said chamber, and a pan located at the open end of said chamber and constituting a support therefor, and means associated with said pan for directing a column of combustible vapor into the open end of said chamber.

3. An oil burner comprising a combus tion chamber having one of its ends open and the other closed and having an imperforate bottom wall and a perforated top wall, a pan located at the open end of said chamber and outwardly offset therefrom and having an open upper side arranged below the top of the combustion chamber, a

vaporizer located within said pan and having a central opening and lateral air passage communicating with said opening, said bottom wall being elevated with respect to the base of the pan, and a nozzle communicating with said vaporizer and pointing in the direction of the central opening therein and toward said bottom wall.

4. An oil burner comprising a combustion chamber open at one end and closed at the other and embodying upper and lower sections provided with contacting flanges, the upper section being perforated, means engaging said flanges to secure the sections together, a pan carried by the lower section and having its upper side open, a vaporizer positioned in said pan, and a nozzle associated with said vaporizer.

5. An oil burner comprising a combustion chamber open at one end and closed at the other and embodying upper and lower semi-cylindrical sections provided with, contacting flanges, the upper section being perforated, means engaging the anges to secure the sections together, a. pan carried by the lower section and having its upper side open, a vaporizer positioned in said pan, and a nozzle associated with said vaporizer.

6. An oil burner comprising a combustion chamber open at one end and closed at the other and embodying semi-cylindrical upper and lower sections, the upper section Y being perforated, means securing the sections together, a pan at the open end of the chamber and formed integrally With the lower section, a vaporizer positioned in said pan, and a nozzle associated with the vaporizer.

7. An oil burner comprising a horizontally elongated combustion chamber open at one end and Closed at the other and provided in its upper side with perforations, a pan formed integrally With the combustion chamber, a vaporizer positioned in the pan, and a nozzle associated with the vaporizer.

8. An oil burner comprising a combust-ion chamber open at one end and provided with perforations in its upper side, a pan formed integrally with the combustion chamber and open at its upper side and provided in its front Wall with an opening, a web extending from the rear side of the pan to the combustion chamber, a vaporizer positioned in the chamber, and a nozzle associated with the vaporizer.

Signed by us at Baltimore, Maryland, this 6th day of February, 1922.

OSCAR FALKENVALDE. CHARLES O. FALKENXVALDE. Witnesses: Y

PORTER H. FLAUTT, CARRIE M. REELY. 

